A late Ediacaran ice age: The key node in the Earth system evolution

Deep‐water first occurrences of Ediacara biota prior to the Shuram carbon isotope excursion in the Wernecke Mountains, Yukon, Canada

“…Second, recent geochemical temperature records for the ca. 590-550 Ma period suggest that while the Shuram CIE interval itself may have been associated with substantial warming, the temperatures prior to and during the appearance of the Avalon assemblage were not actually that hot (Bergmann, Osburn, et al, 2022, in agreement with the worldwide occurrences of glaciogenic sedimentological evidence as seen in Hoffman and Li (2009) and Wang et al (2023)). This is especially true when compared to other times in the Tonian or Cambro-Ordovician where much hotter tropical temperatures of ~35-45°C have been suggested (Bergmann, Boekelheide, et al, 2022;Goldberg et al, 2021;Hearing et al, 2018).…”

“…Consequently, we tentatively lean toward the effect of minor oxygenation coupled with synergistic changes in climate and/or primary productivity as being important in the upslope migration of Ediacaran organisms in the White Sea interval. The timing and climatic effects of possible late Ediacaran glaciation (e.g., Wang et al, 2023) are important in this regard, and further study of all three key drivers of animal energetics, and of the fossil record itself, are required to fully address such questions.…”

Decoding the Puzzle of Late Ediacaran Glaciation(s)

“…In this context, a novel model of continuously dynamic 'GEG' for the Late Ediacaran glaciation was achieved (Figure 2; Wang et al, 2023a, c). In this model, as continents rotated to mid-to-high latitudes where the glaciations happened (Figures 2b -2f), much like the glaciers in the Phanerozoic time (e. g., Wang et al, 2023c), while the continents moving into low latitudes are in a deglacial trend and precipitated some cap carbonates atop the glacial deposits (Wang et al, 2023b). This overleaping of glaciation and carbonate precipitation does not need a Snowball Earth climatic transition and the low-latitude (< 30°) warm regions (continents and oceans) without ice would provid ideal environment for the development of early animals (Figure 2), very different from the small ice holes as life shelter in the Cryogenian Snowball Earth (Hoffman et al, 2017).…”

“…So, any reasonable model must answer the two both questions and would pave a new way to investigate the coevolution of surficial environment and early complex life as discussed in Rooney et al (2020) and Wang et al (2023c). Very coincidentally, the most robust paleomagnetic poles from Laurentia and new key poles from West Africa of Gondwana quantitatively constrained an ~90° amplitude of true polar wander (TPW) from ca.…”